


A Study In Potions

by Mistatim



Category: Harry Potter - J. K. Rowling, Sherlock (TV)
Genre: AU, Gen, Harry Potter - Freeform, I actually watch the episode while writing, Sherlock Holmes - Freeform, sherlock bbc - Freeform, so dialog should be as accurate as possible
Language: English
Status: In-Progress
Published: 2014-03-03
Updated: 2014-03-09
Packaged: 2018-01-14 11:55:39
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 11
Words: 4,089
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1265602
Author URL: https://archiveofourown.org/users/Mistatim/pseuds/Mistatim





	1. Chapter 1

Spells and curses rang through the air as John Watson ran. Screams of Aurors, cries of the injured, bodies everywhere. Off to the side, men and women dropped like stones, hit with unforgivable curses. "Watson!" a voice cried "Watson!".

John Watson sat bolt upright in bed. A dream, he thought while rubbing his temples. Just a dream. He laid back down on his small cot, and tried to get back to sleep.  
In the morning, he grabbed an apple and a cup of coffee, and opened the draw that held his scroll of parchment and his wand. But now he stared at the paper, completely unable yet again, to think of anything to write. It was titled "The Life of John H Watson", but that was as far as he got. Instead, he abandoned his lousy breakfast of an apple and coffee to get ready for his therapy later.

"How's the writing going?" His therapist asked.  
"Hmmm? Oh good, yes, very good." He muttered.  
"You haven't written a word, have you?"  
"You just wrote 'still has trust issues'" He dodged.  
"And you read my writing upside down." She countered. "You see what I mean?"  
He half smiled at her.  
"John. You're a wizard, and it's going to take you a while to adjust to muggle life, but writing down everything that happens to you will help, I promise." She looked at him earnestly.  
He shook his head. "Nothing ever happens to me."


	2. Chapter 2

"What do you mean there's no ruddy Ministry car?"  
"He went to Waterloo, I'm sorry" The girl with the short hair said over the fireplace. "Get a cab."  
"I never get a cab!" The man in the suit retorted.  
"I love you."  
"When?"  
"Get. A. Cab." She left the Floo network.

Half an hour later, the man raised the potion bottle to his lips and drank. A minute later, he was convulsing on the floor as the poison took effect.

"My husband was a happy man." He wife said, barely holding back tears. "That he should take his own life in this way... is a mystery and a shock to all who knew him."

 

Two muggle boys were running through the rain. A cab drives by, and one of the boys runs to stop it. "Hey! Hey!" He chased after it. "Oh, forget it mate. I'm going back home to get my umbrella."  
"Oi wait! You can share mine!" The other says.  
"Two minutes mate!" he calls back over his shoulder.

Now he's in an abandoned gym, shaking hands holding a potions bottle. He slowly uncaps it and takes a drink.  
The headline the next day reads "Boy, 18, kills himself in sports facility."

 

In London's only wizarding dance hall, a women snags her friend's broomstick lock. "She is too drunk to be flying home without the muggles seeing her." She says to her boyfriend.  
"Where is she?" He asks.  
Outside, looking for the key, she hears a cab pull up. Perfect, she thinks. He can take me where I want to go, and then tomorrow I'll come back for the broom.

In an abandoned storage area, she reaches for the potion with trembling fingers and drinks it down.


	3. Chapter 3

"The body of Beth Davenport, understudy for the Director of Wizarding Transport, was found late last night in an abandoned storage facility in Greater London. Preliminary investigations say it was suicide." Sally Donovan brushed her hair back from her face and looked at the reporters. "We can confirm that this apparent suicide closely resembles those of Sir Jeffery Patterson and James Phillimore. In light of this, these instances are being treated as linked. The investigations are still ongoing, but the Detective Inspector for The Minister, DI Lestrade, will take questions now."  
A man with long hair in a blue suit raised his hand. "Uhh, Detective Inspector, how can suicides be linked?"  
"Well they all took the same poison, they were all found in places they had no reason to be, none of them had shown any prior indication..."  
"But you can't have serial suicides." the reporter in the blue suit interrupted.  
"Well apparently you can." Lestrade said.  
"These three people" another reporter chimed in "there's nothing that links them?"  
"No link that we have found as of yet, but we're looking for it." Lestrade answered. "There has to be one."  
Immediately, owls flew through the room, dropping parchment on everyone's laps.  
"If you've all got parchment, please ignore it." Sally said.  
"It just says 'Wrong'" Said the reporter in the blue suit.  
"I know, and if you could just ignore that? Please? Thank you." Sally sighed. "If there are no more questions for Detective Inspector Lestrade, I'm going to bring this session to an end."  
"If they're just suicides, what are you investigating?"  
"As I say, these suicides are clearly linked. But it's... it's an unusual situation, we've got our best people investigating..."  
Immediately all the owls flew through the room again, dropping new parchment on everyone's laps.  
"Says 'Wrong' again." someone muttered.  
"One more question." A female reporter in the back piped up. "Are there any chance these are murders? And if they are, is this the work of a serial killer?"  
"I know you like writing about these, but they do appear to be suicides. We know the difference. The potion was clearly self administered,..."  
"Yes but if these are the work of a serial killer" she interrupted again "how do people keep themselves safe?"  
"Well don't commit suicide." Lestrade answered, clearly tired of stupid questions.  
"Daily Prophet." Sally whispered to him.  
Lestrade rolled his eyes. "All you have to do is exercise reasonable precaution. We are all as safe as we want to be."  
Once again with the owls. But this time, one flew to Lestrade and dropped a parchment on his lap.   
It read "You know where to find me -SH"


	4. Chapter 4

John limped through the park, his thoughts elsewhere, which was probably why he didn’t see Mike Stamford at first.  
“John! John Watson!”  
John turned.  
“It’s me, Mike Stamford! We went to Hogwarts together!”  
“Oh, OH! Yes, hi, Mike.”  
“How are you? Last I heard you were over getting shot at by Death Eaters.”  
“I got shot.”  
Mike faltered at that.  
“So, eh, then, fancy a drink at The Leaky Cauldron?”

John and Mike sat at the pub while Tom brought them their butterbeer. John sipped his slowly, while Mike talked.  
“So, then, where you staying?” Mike asked, pausing his constant drone to ask a question.  
“Hmm?” Said John, looking up from where he was studying the dregs in his glass. “Nowhere yet, haven’t found a place. I can’t live in London though, too expensive.”  
“Have you considered getting a flatmate, then?” Mike raised his eyebrows.  
“A flatmate? Who’d want me for a flatmate?” John shook his head slowly.  
“Funny,” remarked Stamford “You’re the second person to say that to me today.”  
“And who was the first?”


	5. Chapter 5

Sherlock Holmes was shooting pummeling curses at a corpse in St. Mungo’s, while Molly Hooper, the mortician, looked on.  
She trotted down the stairs when he was finished.  
He turned to her. “Ah, Molly. I need to know what bruises form in the next twenty minutes.”  
She look at the body and winced. Looking back up at Sherlock, she started “Listen, I was wondering if-”  
Sherlock interrupted her “Are you wearing lipstick? You weren’t wearing lipstick before.”  
“I… freshened it a little. As I was saying, do you maybe want to have... coffee?”  
“Black, two sugars please, I’ll be in the lab.”  
If Sherlock saw how dejected Molly was, he didn’t acknowledge it. Instead, with a swirl of long black Ravenclaw robes, he strode away.


	6. Chapter 6

Back in his lab, Sherlock studied two blood samples from a man who was supposedly bitten by a Nargle. Bent over his microscope, he saw out of the corner of his eye the two people who had just entered. One was Mike Stamford, a man who he had remarked to earlier about not being able to find a flatmate. The other then must be the flatmate.  
"Bit different from my day." The prospective flatmate remarked upon entering.  
"Mike can I borrow your Floo Powder? I'm out." Sherlock in a startlingly low voice.  
"And what's wrong with the hospital's owl?" Mike questioned.  
"I prefer instant communication." Sherlock replied.  
"Well too bad, it's in my robes."  
"Here," said the other man, "you can use mine."  
Sherlock crossed the room and grabbed the small container he held out.  
"This is an old friend of mine, John Watson." Mike said.  
"The Battle of Hogwarts or at The Ministry?" Sherlock asked John.  
"Sorry?"  
"The battle you were in against Voldemort, Hogwarts or The Ministry?"  
"Hogwarts. How did you...?"  
"Ah Molly," Sherlock interrupted "coffee, thank you. What happened to the lipstick?"  
"It wasn't working for me." Molly said, her eyes not quite meeting Sherlock's.  
"Oh I thought it was a big improvement. Your mouth's too small now."  
"Okay." She said in a small voice, and left the room.  
Sherlock turned back to his microscope and started adjusting the dials.  
"How do you feel about the violin?"  
"I'm sorry?"  
"I play the violin sometimes when I'm thinking, would that bother you? Potential flatmates should know the worst about each other." Sherlock said, looking up at John from his microscope.  
"You told him about me." John said, turning to Mike.  
"Not a word." Mike replied, quite enjoying this whole exchange.  
"Then who said anything about flatmates?" John asked.  
"I did." Sherlock said while putting on his robes with his back to John and Mike. "Wasn't a difficult leap. I remarked to this man that I must be difficult to find a flatmate for, and here he is just after lunch, with an old friend, clearly just returned here from a battle at Hogwarts."  
"How did you know about Hogwarts?" John wondered.  
"Got my eye on a nice little place in central Hogsmeade." Sherlock said, turning around and pulling on a Ravenclaw scarf that was clearly too small for him. "Together we should be able to afford it. Meet there at 7:00 tomorrow. Now sorry, got to dash, I think I left my wand in the mortuary."  
"Is that it?"  
"Is what it?"  
"We've only just met and we're going to go look at a flat together? We don't know a thing about each other. I don't know where we're meeting, I don't even know your name." John said.  
"I know you worked as a medic for the Aurors, and you've recently been invalided home from the Battle Of Hogwarts, I know you've got a brother who's worried about you but you won't go to him for help because you don't approve of him, possibly because he's an alcoholic, more likely because he just walked out on his wife. And I know your therapist thinks your limp is psychosomatic, quite correctly I'm afraid. I think that's enough to be going on, don't you?" Sherlock walked to the door and pulled it open. "The name's Sherlock Holmes and the address is 221B Baker st." He winked and swirled away in a flash of robes and arrogance.


	7. Chapter 7

John knew that Sherlock was a genius, and figured if he was going to look at a flat with the strange man, he should know a thing or two about him. And he would start at the muggle library. Sherlock may be online, and John was muggle born so he knew his way around a computer. He pulled up a seat and logged in. John typed 'Sherlock Holmes' into the browser, and clicked on the first result.

Elsewhere, a woman in pink knelt down and grabbed the poison.


	8. Chapter 8

A cab pulled up just as John Watson knocked on the door to 221B Baker st, in the wizarding part of London. Sherlock Holmes stepped out, and greeted John with a simple 'hello'.  
"Ah, Mr. Holmes." John said, turning around on the doorstep.   
"Sherlock, please." The man in the long grey robes said, extending his hand to shake John's.  
"Well this is a prime spot, right next to Diagon Ally, must be expensive."  
"Well Mrs. Hudson, the landlady, she's giving me a special deal. Owes me a favor. Few years ago her husband got himself sentenced to death in Florida. I was able to help out."  
John blinked. "You stopped her husband from being executed?"  
Sherlock smiled. "Oh no, I ensured it."

The door opened and an old lady stepped out. "Sherlock!" She hugged him.  
"Mrs. Hudson, Dr. John Watson."  
"Hello, come in!" She stepped back and motioned for them to go ahead inside.  
"Thank you." John walked in.  
Sherlock trotted up the stairs and stopped outside a door. John had more trouble, and he limped the whole way.  
When he reached the top, Sherlock swung the door open with all the flourish of a man showing off his own personal creation, and followed John in.  
John was instantly struck by how messy it was, old spellbooks piled up, cushions everywhere, a violin on the couch. But he figured after it was cleaned it would be little and cosy, like a hobbit hole. "Well, this could be very nice." He said. "Very nice indeed."  
"Yes, I think so. My thoughts precisely. So I took the liberty of moving in..."  
"...Soon as we get all this rubbish cleaned up."  
"Oh, oh sorry I didn't mean..." John started.  
"No, no it's quite fine, I'll get all this cleaned up.." Sherlock started moving cushions around, clearly not knowing what he was doing.

"That's... that's a skull." John was looking at the mantle.  
"Friend of mine. When I say friend..." Sherlock shrugged with his hands, swooping over to where Mrs. Hudson had just entered the room.  
"What do you think then Dr. Watson?" She asked. "There's another bedroom upstairs, if you'll be needing two."  
"Of course we'll be needing two." John said.  
"Oh don't you worry" she said, waving her hands "there's all sorts around here. Mrs. Turner next door's got married ones." She waked over to the kitchen table where Sherlock had a bunch of muggle science equipment, as well as cauldrons and flasks. Come to think about it, the flasks might be muggle too. "Oh Sherlock, the mess you've made." She muttered.

John sat down in a red chair by the fire. "I looked you up at the muggle library last night. Thought an unusual man like you who mixes muggle and science might be on the internet."  
"Yes, I am. Did you find anything interesting?"  
"Your website, The Science of Magic and Deduction?"  
"Yes?"  
"You say you can identify an airline pilot by his left thumb, a witch's favorite subject by the length of her hair, and a government worker be it muggle or wizard by the tie?" John asked skeptically.  
"Yes. And I can read your military career by your face and your leg and your brother's drinking habits by your floo powder box."  
"..How?"  
Sherlock looked about to answer, but Mrs. Hudson cut in. "So how about those suicides then Sherlock? I thought that'd be right up your street. Three exactly the same."  
"Four." Sherlock answered. "There's been a fourth, and something's different about it this time."


	9. Chapter 9

Lestrade ran up the stairs to 221B.  
"Where?" Sherlock said, whirling around.  
"Brixton, Lauriston Gardens." Lestrade replied.  
"What's new about this one? You wouldn't have come to get me if there wasn't something different."  
"You know how the never leave notes? This one did. Will you come?"  
"Hmm, who's on spell forensics?"  
"... Anderson"  
"Anderson won't work with me."  
"Well he won't be your assistant!"  
"I need an assistant."  
Lestrade sighed. "Will you come?"  
"Not in a Ministry car, I'll be right behind."  
"Thank you." Lestrade turned and left through the door without so much as a hello toward the other occupants of the room.  
John looked back and forth between where Lestrade stood and where Sherlock was standing at the window. Suddenly Sherlock lept into the air with a broad grin on his face and exclaimed "Oh! Four serial suicides and now a note! It's Christmas! Mrs. Hudson, I'll be late, might need some food."  
"I'm your landlady dear, not your housekeeper." She replied.  
"Something cold and wand-made will do! John, make yourself at home, have a cup of tea, a biscuit. Don't wait up!" He swirled out the door in a flash of robes and improper happiness.  
"Look at him dashing about when there's a body, it's not right. Tell you what, I'll make you that cuppa, you rest your leg."  
"DAMN MY LEG! Sorry I'm so sorry, it's just sometimes this bloody" he hit his leg with his cane "thing is so annoying." He grimaced.  
"It's okay dear, I understand. I've got a hip."  
"A cup of tea would be lovely, thank you."  
"Just this once dear, I'm not your housekeeper."  
"And a couple of biscuits too, if you've got them."  
"Not your housekeeper!" She called back from the kitchen.

"You're a doctor. In fact, you were an Auror too." said a deep voice from the doorway.  
"Yes." John Watson said, pulling himself to his feet.  
"Any good?"  
"Very good."  
"Seen a lot of injuries then? Violent deaths?" said Sherlock, coming closer.  
"Yes."  
"Bit of trouble too, I bet." Murmured Sherlock, now barely a foot away.  
"Of course. Enough to last a lifetime, far too much."  
Sherlock smiled. "Want to see some more?"  
"Oh god, yes."

"Forget about the tea, Mrs. Hudson!" John called as they went down the stairs. "I'm off!"  
"Both of you?"  
"Yes!" cried Sherlock, grabbing her by the shoulders. "There's no point in sitting around at home when there's finally something fun going on!" He kissed her cheek and stepped back.  
"Look at you all happy. It's not decent."  
"Who CARES about decent!? The game, Mrs. Hudson, is ON!" and he strode triumphantly away with John like a puppy at his heel.


	10. Chapter 10

Sherlock stepped outside and hailed the Knight bus, holding the door for John to get in first. They sat in the back of the empty bus, John staring in wonder at the man he knew nothing about. Sherlock sighed and looked his way. "Okay, so you've got questions?"  
"Yeah," John replied "where are we going?"  
"Crime scene. Next?"  
"Who are you? What do you do?" John squinted at him.  
"What do you think?" Sherlock's expression was one of a man asked the same thing many times, not necessarily by the most approving people.  
"I'd say, private detective?"  
"But?"  
"But the police don't go to private detectives."  
Sherlock smiled. "I'm a consulting detective, only one in the world. In fact, I invented the job."  
"What does that mean?"  
"It means when the Department Of Magical Law Enforcement is out of their depth, which is always, they consult me."  
"The Department Of Magical Law Enforcement doesn't consult amateurs!"  
Sherlock looked positively pleased to have an excuse to show off. "When I met you for the first time yesterday, I said Hogwarts, or the Ministry."  
"Yes, how did you know?"  
"I didn't know, I saw. your haircut, the way you hold yourself says Auror, your conversation as you entered the room says taught at St. Mungo's, so Auror doctor, obviously. Visible injuries, so fighting. Your limp's bad, but you don't ask for a chair when you stand, like you've forgotten about it, so it's at least partly psychosomatic. That says original circumstances of the injury were traumatic, so cursed in battle, then. Injures, Auror, most recent fights were against Voldemort in either Hogwarts, or the Ministry."  
"You said I had a therapist."  
"You've got a psychosomatic limp, of course you have a therapist. then there's your brother."  
"Hmmm?"  
"Your Floo powder bottle, expensive, gold flakes, jet black with what is presumably your family emblem on the lid. But you're looking for a flatshare, you wouldn't waist money on this, it's a gift then. Scratches, not one, many over time. It's been in the same pocket as keys, and coins. The man sitting next to me wouldn't treat his one luxury item like this, so it's had a previous owner. Owner must have been in your family because of the emblem, hedgehog, I like it. Anyway, another engraving on the bottom proves this, To: Harry Watson From: Clara. Now Clara, who's Clara? Three kisses says it's a romantic attachment. The expense of the bottle says wife not girlfriend. She must have given it to him recently, this type of bottle wasn't popular until six months ago. Marriage in trouble then, six months on he's just given it away. If she left him, he would have kept it. People do, sentiment. No, he wanted rid of it, he left her. He gave it to you, wants you to stay in touch. You want cheap accommodation, but you're not going to your brother for help, that says you've got a problem with him. Maybe you liked his wife, maybe you don't like his drinking." Sherlock spoke in rapid fire, barely taking in breath.  
"How could you possibly know about the drinking?"  
Sherlock smirked. "Shot in the dark, really. Good one though. The bottle lid has tiny scuffmarks around the edge where he's gone to screw it on. Rarely see a sober man's with them, never see a drunks without. There you go, see, you were right."  
John looked incredulous. "I was right?"  
Sherlock looked at him. "The Department doesn't consult amateurs."  
"That," John began. Sherlock looked away, ready for John to tell him off, "was amazing."  
"Really?" Sherlock looked surprised.  
"Oh, course. It was extraordinary."  
"That's not what people normally say."  
"What do they normally say?"  
"Piss off."  
John turned to the window so Sherlock wouldn't see that he was smiling. Little did he know that Sherlock was doing the same.


	11. Chapter 11

Sherlock and John exited the Knight Bus, paid Ernie, and started walking toward the crime scene. "Did I get anything wrong?" Sherlock asked.  
"Harry and me don't get on, never have. Clara and Harry split up about three months ago, they're getting a divorce. Harry's a drinker."  
"Spot on then, didn't expect to be right about everything."  
"Harry is short for Harriet."  
Sherlock stopped in his tracks. "Harry's your sister."  
"Look, what exactly am I supposed to be doing here?"  
"Sister!" Sherlock hissed.  
"No, really, what exactly am I supposed to be doing here?"  
"There's always something." Sherlock muttered to himself.

"Hello freak." Sally Donovan called out when they reached the tape marking the scene.  
Sherlock ignored her. "I'm here to see DI Lestrade."  
"Why?"  
"I was invited."  
"Why?"  
"I think he wants me to take a look." Sherlock said snarkily.  
"Well you know what I think, don't cha?"  
"Always, Sally. Even know you didn't make it home last night."  
John didn't want to hear them fight, so he walked over to the tape and pulled it up.  
"Uh, wait, who's this?" Sally asked, pointing to John.  
"Colleague of mine, Dr. Watson." Sherlock answered. "Dr. Watson, Sgt. Sally Donovan. Old... friend."  
"A colleague?" She said in an incredulous voice. "How'd you get a colleague?" She turned to John. "What, did he follow you home?"  
John shifted uncomfortably. "Would it be better if I just waited...?"  
"No" Sherlock said, lifting up the tape and turning away.  
Sally pulled out her enchanted coin and called Lestrade. "Freak's here. Bringing him in."  
John knew the Department took the idea of the coins from Hermione and just altered it to transmit sound instead of numbers, though they'd never say.

As Sally lead them to the big house, Sherlock spun around, taking everything in. Three people walked out of the house in front of him, and Sherlock stopped short.  
"Ah, Anderson. Here we are again." Sherlock said to a tall man with a pinched face and dark hair.  
"It's a crime scene, I don't want it contaminated." He said in a snarky voice. "Are we clear on that?"  
"Quite clear. And is your wife away for long?"  
"Oh don't pretend you worked that out. Someone told you."  
"Your deodorant told me that."  
"What?"  
"It's for men."  
"Well of course it's for men, I'm wearing it!"  
"So's Sgt. Donovan."  
Anderson looked at her, startled. He turned back to Sherlock. "Whatever you're trying to imply..."  
"Oh, I'm not implying anything. I'm sure Sally came round for a nice little chat." He glanced down at her legs as he walked by. "And I'm assuming she scrubbed your floors going by the state of her knees." He smirked and strode in to the building. John shot an apologetic glance toward Sally, and followed him in.


End file.
